Results 1 to 4 of 4
  1. #1
    Join Date
    Jan 2013
    Posts
    9

    Tool to measure power on 3-phase motors

    Hey all,
    which tool do you use to measure power of three phase motors?

    Or do you just take current readings on each phase + voltage readings and do the calculation by yourself?

    Greatings,
    Dirk

  2. #2
    Join Date
    Aug 2009
    Location
    Jurupa Valley, CA
    Posts
    1,787
    Quote Originally Posted by goe.di View Post
    Hey all,
    which tool do you use to measure power of three phase motors?

    Or do you just take current readings on each phase + voltage readings and do the calculation by yourself?

    Greatings,
    Dirk
    simply reading voltage and current won't give you power (W). It will give you apparent power (VA). A power meter has to look at the phase shift between voltage and power to determine the actual power used. For this, the only thing to use is a power meter (usually installed as a fixed device, not generally used in a portable fashion)

    There are 'portable' units available, but they are usually geared towards power quality analysis and datalogging.

  3. #3
    Join Date
    Jan 2013
    Posts
    9
    You are right it will give you apparent power but with an assumed cosPhi (0,85-0.9) you can "estimate" the real power. Heard from several people doing that.

    So you just take amp draw readings to make sure that the "fixed" devices on 3-Phase motors show the right values?

    How on one phase motors?

  4. #4
    Join Date
    Jul 2001
    Location
    Canada
    Posts
    1,826
    Fluke 433 Three-phase Power Quality Analyzer


Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Comfortech Show Promo Image

Related Forums

Plumbing Talks | Contractor Magazine
Forums | Electrical Construction & Maintenance (EC&M) Magazine
Comfortech365 Virtual Event